Heat exchanger for an air conditioner and an air conditioner having the same

ABSTRACT

A heat exchanger for an air conditioner and an air conditioner having the same are provided. The heat exchanger may include at least one heat exchange device, the heat exchange device comprising a lower header provided therein with a lower flow path; an upper header provided therein with an upper flow path; and a plurality of flat tubes provided therein with a plurality of flow paths that communicates with the lower flow path and the upper flow path. The upper flow path may be partitioned into a first lower flow path with which a portion of the plurality of flat tubes may communicate, and a second lower flow path with which a remaining portion of the plurality of flat tubes may communicate. Each of an internal sectional area of the upper header and an internal sectional area of the lower header may be 0.7 times or more as large as a sum of sectional areas of flow paths in the plurality of flat tubes forming one path.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application claims priority to Korean Application No. 10-2012-0124328 filed in Korea on Nov. 5, 2012 and Korean Application No. 10-2013-0069690 filed in Korea on Jun. 18, 2013, the subject matter of each of which is incorporated herein by reference.

BACKGROUND

1. Field

A heat exchanger for an air conditioner and an air conditioner having the same are disclosed herein.

2. Background

Heat exchangers for air conditioners and air conditioners having the same are known. However, they suffer from various disadvantages.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments will be described in detail with reference to the following drawings in which like reference numerals refer to like elements, and wherein:

FIG. 1 is a schematic view of an air conditioner including a heat exchanger according to an embodiment;

FIG. 2 is a side view of an inside of an indoor device in which a heat exchanger according to an embodiment may be installed;

FIG. 3 is a side view of a heat exchanger for an air conditioner according to an embodiment;

FIG. 4 is an exploded perspective view of the heat exchanger of FIG. 3;

FIG. 5 is a front view of the heat exchanger of FIG. 3;

FIG. 6 is a sectional view taken along line VI-VI of FIG. 3;

FIG. 7 is a sectional view taken along line VII-VII of FIG. 3;

FIG. 8 is a sectional view taken along line VIII-VIII of FIG. 5;

FIG. 9 is a sectional view taken along line IX-IX of FIG. 5;

FIG. 10 is a graph illustrating a performance ratio of a heat exchanger according to a length ratio of a longitudinal width of a heat exchange region to a transverse width of the heat exchange region in a heat exchanger for an air conditioner according to an embodiment;

FIG. 11 is a sectional view of an inside of a header of a heat exchanger for an air conditioner according to an embodiment;

FIG. 12 is a graph illustrating a mal-distribution ratio according to a ratio of a sum of sectional areas of flow paths of a plurality of flat tubes forming one path to an internal sectional area of a header according to an embodiment;

FIG. 13 is a front view of a plurality of communication holes and a separator according to an embodiment;

FIG. 14 is a graph illustrating a cooling efficiency according to a ratio of an area of a separator to a sum of sectional areas of a plurality of communication holes in a heat exchanger for an air conditioner according to an embodiment;

FIG. 15 is a perspective view of a heat exchanger for an air conditioner according to another embodiment;

FIG. 16 is an exploded perspective view of the heat exchanger of FIG. 15;

FIG. 17 is a sectional plan view of an upper header of the heat exchanger of FIG. 15; and

FIG. 18 is a sectional plan view of a lower header of the heat exchanger of FIG. 15.

DETAILED DESCRIPTION

Embodiments may be described with reference to appended drawings. For the description of the embodiments, the same names and symbols may be used for the same structure and an additional description according thereto may not be provided.

In general, a heat exchanger may be used as a condenser or an evaporator in a refrigerating cycle device including a compressor, a condenser, an expansion device, and an evaporator. Such a heat exchanger may be installed in, for example, a vehicle, a refrigerator, or an air conditioner, and may exchange heat of a refrigerant with air.

The heat exchanger may be classified as a fin-and-tube type heat exchanger or a micro channel type heat exchanger. The heat exchanger may include a tube, through which the refrigerant may pass, a heat member connected to the tube, and a header that distributes the refrigerant to the tube. A refrigerant introducing pipe that guides the refrigerant to the header may be connected to the heat exchanger, and a refrigerant discharging pipe that discharges the refrigerant from the header may be connected to the heat exchanger.

FIG. 1 is a schematic view of an air conditioner including a heat exchanger according to an embodiment. As shown in FIG. 1, the air conditioner 1 may include a compressor 2 that compresses a refrigerant, an outdoor heat exchanger 4 that exchanges heat of the refrigerant with exterior air, an expansion device 6 that expands the refrigerant, and an indoor heat exchanger 8 that exchanges heat of the refrigerant with interior air or air in an interior space. In the air conditioner 1, the refrigerant compressed by the compressor 2 may pass through the outdoor heat exchanger 4 so that the heat of the refrigerant may be exchanged with the exterior air and be condensed. In this case, the outdoor heat exchanger 4 may function as a condenser. The refrigerant condensed in the outdoor heat exchanger 4 may move into the expansion device 6 so that the expansion device 6 may expand the condensed refrigerant. The refrigerant expanded by the expansion device 6 may pass through the indoor heat exchanger 8 and the heat of the refrigerant may be exchanged with interior air to be evaporated. In this case, the indoor heat exchanger 8 may function as an evaporator to evaporate the refrigerant. The refrigerant evaporated in the indoor heat exchanger 8 may be recovered to the compressor 2. The refrigerant may circulate via the compressor 2, the outdoor heat exchanger 4, the expansion device 6, and the indoor heat exchanger 8 to cool the interior air.

A flow path 11, for example, a gas pipe, that guides the refrigerant having passed through the indoor heat exchanger 8 to the compressor 2 may be provided. An accumulator 9 may be installed at, on, or in the flow path 11. Liquefied refrigerant may be accumulated in the accumulator 9.

A flow path through which the refrigerant may pass may be formed in the indoor heat exchanger 8. A flow path 10, for example, a liquid pipe, that guides the refrigerant having passed through the expansion device 6 to a first end of the refrigerant flow path may be connected to the indoor heat exchanger 8. The flow path 11 may guide the refrigerant evaporated in the indoor heat exchanger 8 and may be connected to a second end of the flow path of the indoor heat exchanger 8.

The air conditioner 1 may be a separate or split type air conditioner in which an indoor device I is separated from an outdoor device O. In this case, the compressor 2 and the outdoor heat exchanger 4 may be installed inside the outdoor device O, the expansion device 6 may be installed at or in the indoor device I or the outdoor device O, and the indoor heat exchanger 8 may be installed inside the indoor device I.

An outdoor fan 12, which may blow exterior air to the outdoor heat exchanger 8, may be installed in the outdoor device O. The exterior air blown to the outdoor heat exchanger 4 from the outdoor fan 12 may condense the refrigerant passing through the outdoor heat exchanger 4.

An indoor fan 13 that blows interior air to the indoor heat exchanger 8 may be installed in the indoor device I. The interior air blown to the indoor heat exchanger 8 from the indoor fan 13 may condense the refrigerant passing through the indoor heat exchanger 8.

FIG. 2 is a side view of an inside of an indoor device in which a heat exchanger according to an embodiment may be installed. As shown in FIG. 2, the indoor device I may include a casing 16 that forms an outer appearance of the indoor device I. An air introduction port 14 and an air discharge port 15 may be formed in the casing 16. The casing 16 may be formed by an assembly having a plurality of members. The casing 16 may include an introduction panel 17 formed therein with the air introduction port 14 and a discharge panel 18 formed therein with the air discharge port 15. The casing 16 may include a base 19 that supports a load of the indoor device I. The casing 16 may further include a front panel that forms a front appearance of the air conditioner 1.

A heat exchanger, such as indoor heat exchanger 8 of FIG. 1, and a fan, such as indoor fan 13 of FIG. 1, may be installed inside the casing 16. In such a case, when driving the indoor fan 13, interior air may be introduced into the casing 16 through the air introduction port 14, and may pass through an inside of the casing 16 and may then be discharged to the air discharge port 15. The indoor heat exchanger 8 may exchange heat of the interior air introduced through the air introduction port 14 with refrigerant upon driving the indoor fan 13. The indoor heat exchanger 8 may be substantially longitudinally aligned or oriented inside the casing 16. The indoor heat exchanger 8 may be substantially vertically oriented or inclined inside the casing 16.

As discussed further hereinbelow, the heat exchanger may include one or more heat exchange devices HU1 and HU2. The heat exchanger may include one or more lower headers 30 and one or more upper headers 40 vertically spaced from each other. The one or more lower headers 30 may be connected to the one or more upper headers 40 by a plurality of flat tubes 50 and 70.

The heat exchanger according to embodiments may function as at least one of the outdoor heat exchanger 4 or the indoor heat exchanger 8. For example, the heat exchanger according to embodiments may be applicable as the indoor heat exchanger 8 into which a two-phase refrigerant may be introduced and may function as an evaporator. When the air conditioner is a cooling and heating concurrent type air conditioner, the indoor heat exchanger 8 may function as the evaporator during a cooling operation mode, while the outdoor heat exchanger 4 may function as the evaporator during a heating operation mode. In this case, the indoor heat exchanger 8 and the outdoor heat exchanger 4 may serve as the heat exchanger of the air conditioner according to embodiments, respectively.

FIG. 3 is a side view of a heat exchanger for an air according to an embodiment. The heat exchanger for an air conditioner according to an embodiment may include a heat exchange device through which refrigerant may pass and heat-exchange with air. The heat exchanger for an air conditioner may include an inlet pipe 100 connected to the flow path 10 shown in FIG. 1 and an outlet pipe 110 connected to the flow path 11 shown in FIG. 1.

The heat exchanger according to embodiments may include at least one heat exchange device HU1. Both the inlet pipe 100 and the outlet pipe 110 may be connected on the heat exchange device HU1. In this case, the refrigerant in the flow path 10 may be moved or flow in the order of the inlet pipe 100, the heat exchange device HU1, and the outlet pipe 110, and then may be moved or flow to the flow path 11.

The heat exchanger according to embodiments may include a plurality of heat exchange devices HU1 and HU2 through which a refrigerant R may sequentially pass. The plurality of heat exchange devices HU1 and HU2 may be disposed at front and rear sides with respect to a direction of air movement. Further, the inlet pipe 100 may be connected to a first heat exchanger device HU1 of the plurality of heat exchange devices HU1 and HU2, while the outlet pipe 110 may be connected to a second heat exchanger of the plurality of heat exchange devices HU1 and HU2. In this case, the refrigerant R in the flow path 10 may be moved or flow in the order of the inlet pipe 100, the heat exchanger HU1, the heat exchanger HU2, and the outlet pipe 110 and may then be moved or flow to the flow path 11. Use of the plurality of heat exchange devices HU1 and HU2 may minimize a height of the heat exchanger.

The plurality of heat exchange devices HU1 and HU2 may include a front or first heat exchange device HU1, through which the refrigerant R may first pass, and a rear or second heat exchange device HU2, through which the refrigerant R may pass later. The inlet pipe 100 may be connected to the front or first exchange device HU1, and the outlet pipe 110 may be connected to the rear or second heat exchange device HU2. The heat exchanger may be installed such that air passes through the front or first exchange device HU1 after the air passes through the rear or second heat exchange device HU2. Alternatively, the heat exchanger may be installed such that air first passes through the front or first exchanger device HU1 and then passes through the rear or second heat exchange device HU2.

Hereinafter, for purposes of convenience, when the front or first exchange device HU1 is distinguished from the rear or second heat exchange device HU2, the embodiment will be discussed on the assumption that one is referred to as ‘front exchange device HU1’ and the other is referred to as ‘rear heat exchange device HU2’, and a common configuration of the front exchange device HU1 and the rear heat exchange device HU2 is referred to as ‘heat exchange device HU1/HU2’.

FIG. 4 is an exploded perspective view of the heat exchanger of FIG. 3. FIG. 5 is a front view of the heat exchanger of FIG. 3. FIG. 6 is a sectional view taken along line VI-VI of FIG. 3. FIG. 7 is a sectional view taken along line VII-VII of FIG. 3. FIG. 8 is a sectional view taken along line VIII-VIII of FIG. 5. FIG. 9 is a sectional view taken along line IX-IX of FIG. 5.

The heat exchange devices HU1 and HU2 may each include the lower header 30, the upper header 40 spaced apart from the lower header 30, a plurality of the flat tubes 50 and 70, which may communicate an inside of the lower header 30 with an inside of the upper header 40, and a fin 90 disposed between the plurality of flat tubes 50 and 70. The lower header 30 may be formed therein with lower flow paths PL1 and PL2 through which the refrigerant may pass. The upper header 40 may be formed therein with an upper flow path PU through which the refrigerant may pass. The plurality of flat tubes 50 and 70 may be formed therein with flow paths that communicate with the lower flow paths PL1 and PL2, and the upper flow path PU, respectively. The flow paths formed in the plurality of flat tubes 50 and 70 may include heat exchange flow paths through which the refrigerant may pass so that heat of the refrigerant may be exchanged with air.

The lower header 30 may extend substantially longitudinally in a direction X substantially perpendicular to a moving direction Z of the air. The lower flow paths PL1 and PL2 may extend substantially longitudinally in a longitudinal direction of the lower header 30. The lower header 30 may be provided with a plurality of lower slits 32, which may be formed through or corresponding to lower portions of the flat tubes 50 and 70. The plurality of lower slits 32 may be formed at an upper portion of the lower header 30. A same number of lower slits 32 may be formed as the corresponding number of flat tubes 50 and 70. The plurality of lower slits 32 may be spaced apart from each other in a longitudinal direction of the lower header 30.

The lower flow paths PL1 and PL2 may be partitioned into a first lower flow path PL1 with which a portion of the plurality of flat tubes 50 and 70 may communicate and a second lower flow path PL2 with which a remaining portion of the plurality of flat tubes 50 and 70 may communicate. A partition 33 may be disposed in the lower header 30 to partition an inside of the lower header 30, for example, to the left and right. The partition 33 may partition the inside of the lower header 30 into the first lower flow path PL1 and the second lower flow path PL2. A partition insertion hole 34 may be formed in the lower header 30. The partition 33 may be inserted into an upper portion of the partition insertion hole 34 to be installed therein.

The upper header 40 may extend substantially longitudinally parallel with or to the lower header 30. The upper header 40 may be vertically spaced apart from an upper portion of the lower header 30. The upper header 40 may be provided with the upper flow path PU so that the refrigerant may move therein substantially in the longitudinal direction X. The upper header 40 may be provided with a plurality of upper slits 42, which may be formed through or corresponding to upper portions of the plurality of flat tubes 50 and 70. The plurality of upper slits 42 may be formed at a lower portion of the upper header 40. A same number of upper slits 42 may be formed as the corresponding number of flat tubes 50 and 70. The plurality of upper slits 42 may be spaced apart from each other in a substantially longitudinal direction of the upper header 40.

One upper flow path PU may be longitudinally formed in the upper header 40 in a substantially horizontal direction. The refrigerant may be introduced into the upper flow path PU through a portion of the plurality of flat tubes 50 and 70. Next, the refrigerant may collide with an inner top wall 44 of the upper header 40 and be moved in a longitudinal direction of the upper flow path PU along the upper flow path PU. The refrigerant moved along the upper flow path PU may be moved into a remaining portion of the plurality of flat tubes 50 and 70.

A plurality of flow paths C1, C2, and C3 may be formed in the plurality of flat tubes 50 and 70, respectively. The plurality of flat tubes 50 and 70 may include flat individual tubes 60 to 69 that communicate the first lower flow path PL1 with the upper flow path PU. The flat tubes 60 to 69 may form a first flat tube group 50. The plurality of flat tubes 50 and 70 may further include individual flat tubes 80 to 89 that communicate the second lower flow path PL2 with the upper flow path PU. The flat tubes 80 to 89 may form a second flat tube group 70.

In the heat exchange devices HU1 and HU2, when the refrigerant is introduced into the first lower flow path PL1, the refrigerant introduced into the first lower flow path PL1 may be distributed into the flat tubes 60 to 69 forming the first flat tube group 50 and be ascended or flow upward, and may pass through the flat tubes 60 to 69 forming the first flat tube group 50. The refrigerant may pass through the flat tubes 60 to 69 forming the first flat tube group 50 and then be moved upward into the upper flow path PU. The refrigerant moved into the upper flow path PU from the flat tubes 60 to 69 may be combined in the upper flow path PU and be horizontally moved or flow inside the upper flow path PU. The refrigerant in the upper flow path PU may be distributed into the flat tubes 80 to 89 forming the second flat tube group 70, be descended or flow downward, and pass through the flat tubes 80 to 89. The refrigerant may pass through the flat tubes 80 to 89 and then be descended to or flow into the second lower flow path PL2. The refrigerant moved into the flat tubes 80 to 89 may be combined in the second lower flow path PL2.

Alternatively, in the heat exchange devices HU1 and HU2, when the refrigerant is introduced into the second lower flow path PL2, the refrigerant introduced into the second lower flow path PL2 may be distributed into the flat tubes 80 to 89 forming the second flat tube group 70 and be ascended or flow upward, and may pass through the flat tubes 80 to 89 forming the second flat tube group 70. The refrigerant may pass through the flat tubes 80 to 89 forming the second flat tube group 70 and then be moved upward into the upper flow path PU. The refrigerant moved into the upper flow path PU from the flat tubes 80 to 89 forming the second flat tube group 70 may be combined in the upper flow path PU and be horizontally moved inside the upper flow path PU. The refrigerant in the upper flow path PU may be distributed into the flat tubes 60 to 69 forming the first flat tube group 50, be descended or flow, and pass through the flat tubes 60 to 69. The refrigerant may pass through the flat tubes 60 to 69 and then be descended to or flow into the first lower flow path PL1. The refrigerant moved into the flat tubes 60 to 69 may be combined in the first lower flow path PL1.

For example, if the heat exchange devices HU1 and HU2 include a total of twenty flat tubes, respectively, the first flat tube group 50 may include ten flat tubes 60 to 69, and the second flat tube group 70 may include ten flat tubes 80 to 89. The heat exchange devices HU1 and HU2 may form one path including in an order the first lower flow path PL1, the first flat tube group 50, the upper flow path PU, the second flat tube group 70, and the second lower flow path PL2. When the refrigerant is first introduced into the second lower flow path PL2, the heat exchange devices HU1 and HU2 may form one path formed in order of the second lower flow path PL2, the second flat tube group 70, the upper flow path PU, the first flat tube group 50, and the first lower flow path PL1. In this case, the number of flat tubes forming one path in the heat exchange devices HU1 and HU2 may be twenty.

As another example, the heat exchange devices HU1 and HU2 may include 30 flat tubes, the first flat tube group 50 may include 15 flat tubes, and the second flat tube group 70 may include 15 flat tubes. In this case, as in the case including a total of 20 flat tubes, the heat exchange devices HU1 and HU2 may form one path formed in the order of the first lower flow path PL1, the first flat tube group 50, the upper flow path PU, the second flat tube group 70, and the second lower flow path PL2, or one path formed in the order of the second flow path PL2, the second flat tube group 70, the upper flow path PU, the first flat tube group 50, and the first lower flow path PL1. In this case, the number of flat tubes forming one path in the heat exchange devices HU1 and HU2 may be thirty.

However, the number of flat tubes is not so limited. Several numbers of flat tubes, such as 10, 24, 36, and 40 flat tubes, may be provided. It has been illustrated in FIGS. 4 and 5 that ten flat tubes 60 to 69 form the first flat tube group 50 and ten flat tubes 80 to 89 form the second flat tube group 70 for the purpose of convenience or clarity.

The inlet pipe 100 may guide the refrigerant to one of the lower header 30 or the upper header 40, and the outlet pipe 110 may guide the refrigerant to be discharged from one of the lower header 30 or the upper header 40. When the heat exchanger for an air conditioner according to embodiments includes one heat exchange device HU1, the inlet pipe 100 to introduce and guide the refrigerant may guide the refrigerant to one of the first lower flow path PL1 or the second lower flow path PL2, and the outlet pipe 110 to discharge and guide the refrigerant may discharge the refrigerant from the other of the first lower flow path PL1 or the second lower flow path PL2.

When the heat exchanger for an air conditioner according to embodiments includes a plurality of heat exchange devices HU1 and HU2, an inlet pipe 100 to introduce and guide the refrigerant may be connected to the first lower flow path PL1 formed at or in the lower header 30 of a first heat exchanged device HU1 of the plurality of heat exchange devices HU1 and HU2, and an outlet pipe 110 to discharge and guide the refrigerant may be connected to the first lower flow path PL1 formed at the lower header 30 of a second heat exchange device HU2 of the heat exchange devices HU1 and HU2. The second lower flow path PL2 formed at the lower header 30 of the first heat exchange device HU1 may communicate with the second lower flow path PL2 formed at the lower header 30 of the second heat exchange device HU2 through a plurality of communication holes 35, 36, 37, and 38.

The inlet pipe 100 may introduce and guide the refrigerant in a direction perpendicular to a longitudinal direction of the plurality of flat tubes 50 and 70. The inlet pipe 100 may be longitudinally disposed in a direction perpendicular to the longitudinal direction Y of the plurality of flat tubes 50 and 70 and in a direction Z perpendicular to the longitudinal direction X of the lower header 30. In this case, the refrigerant may be introduced into the lower header 30 parallel with a flow direction of air, and may be horizontally sprayed inside the lower header 30 to be moved in substantially left and right directions. When the refrigerant introduced into the lower header 30 is horizontally sprayed inside the lower header 30 to be moved in left and right directions, the inlet pipe 100 may uniformly distribute the refrigerant, and may be longitudinally disposed in a direction perpendicular to a longitudinal direction Y of the plurality of flat tubes 50 and 70 and in a direction Z perpendicular to the longitudinal direction X of the lower heater 30. One inlet pipe 100 may guide the refrigerant to a substantially central position of the first lower flow path P1. The inlet pipe 100 may include a common pipe and a plurality of branch pipes branched from the common pipe. The common pipe may be connected to the flow path 10, and the plurality of branch pipes may guide the refrigerant to a plurality of positions along the lower flow path P1.

The inlet pipe 100 may be substantially longitudinally disposed in a direction substantially perpendicular to a longitudinal direction Y of the plurality of flat tubes 50 and 70 and in a longitudinal direction of the lower header 30. In this case, the refrigerant may be moved in a substantially longitudinal direction of the lower heater 30 aside the lower header 30 and be introduced into the lower header 30, and may be substantially horizontally moved inside the lower header 30. As the lower header 30 is partitioned into a first lower flow path PL1 and a second lower flow path PL2, lengths of the first lower flow path PL1 and the second lower flow path PL2 may be shorter than those in a case where an inside of the lower header 30 is not partitioned to the left and right, and a phenomenon where liquefied refrigerant is concentrated to an opposite side of the inlet pipe 100 may be minimized. That is, even when the inlet pipe 100 is longitudinally disposed in a longitudinal direction X of the lower header 30, the lengths of the first lower flow path PL1 and the second lower flow path PL2 may be short, so the refrigerant may be uniformly sprayed to the plurality of flat tubes 50 and 70.

The outlet pipe 110 may discharge and guide the refrigerant in a direction perpendicular to the plurality of flat tubes 50 and 70. The outlet pipe 110 may be substantially longitudinally disposed in a direction substantially perpendicular to the longitudinal direction Y of the plurality of flat tubes 50 and 70 and in a direction Z substantially perpendicular to the longitudinal direction X of the lower header 30. The outlet pipe 110 may be substantially longitudinally disposed in a direction substantially perpendicular to the longitudinal direction Y of the plurality of flat tubes 50 and 70 and in the longitudinal direction X of the lower header 30.

Referring to FIG. 5, a performance ratio of the heat exchanger for an air conditioner according to embodiments may be determined according to a size and a shape of a heat exchange area Aheat. The heat exchange area Aheat may be an area in which heat of the plurality of flat tubes 50 and 70 and the fins 90 may be exchanged with air. The heat exchange area Aheat may include a whole area between the lower header 30 and the upper header 40, or an area in which the plurality of flat tubes 50 and 70 and the fins 90 are substantially located except for a partial left region and a partially right area among the whole area between the lower header 30 and the upper header 40.

A height of the plurality of flat tubes 50 and 70 in the heat exchange area Aheat formed between the lower header 30 and the upper header 40 may be a longitudinal width L. A distance between a left end or edge of a flat tube 89, which may be horizontally located at a left end or edge of the plurality of flat tubes 50 and 70 and a right end or edge of a flat tube 60, which may be located at a right end or edge of the plurality of flat tubes 50 and 70 in the heat exchange area Aheat may be a transverse width W. The longitudinal width L of the heat exchange area Aheat may be longer than the transverse width W thereof. The longitudinal width L and the transverse width W will be described in more detail with reference to FIG. 10.

Further, in the heat exchanger for an air conditioner according to embodiments, each of an internal sectional area Aheader of the upper header 40 and an internal sectional area Aheader of the lower header 30 may be approximately 0.7 times or more as large as a sum of sectional areas of flow paths in a plurality of flat tubes constituting one path.

The sum of sectional areas of flow paths may be determined by a following Equation 1:

Acell=Tn×Cn×A  [Equation 1]

where, Acell is a sum of sectional areas of flow paths, Tn is a number of flat tubes forming one path, Cn is a number of flow paths C1, C2, and C3 formed at or in the plurality of flat tubes, and A is an area of a flow path.

In the heat exchanger for an air conditioner according to embodiments, sectional areas A of flow paths C1, C2, and C3 formed in each of the plurality of flat tubes may be the same as each other. In this case, A may be a sectional area of one flow path. In the heat exchanger for an air conditioner according to embodiments, sectional areas A of flow paths C1, C2, and C3 formed in each of the plurality of flat tubes may be different from each other. In this case, A may be an average sectional area of flow paths C1, C2, and C3 formed in one flat tube. That is, Cn×A in Equation 1 may be a sum of sectional areas of a plurality of flow paths C1, C2, and C3 formed in one flat tube.

For example, when a total of seven flow paths C1, C2, and C3 are formed in each of the plurality of flat tubes 50 and 70, a total of ten flat tubes may communicate with the first lower flow path PL1 of the lower path PL2, and a sectional area of the flow path is A (average sectional area when sectional areas of flow paths are different from each other), the number Tn of flat tubes forming one path may be ten, the number of the flow paths C1, C2, and C3 may be 7, and a sum Acell of sectional areas of the flow paths may be 10×7×A. In this case, each of an internal sectional area Aheader of the upper header 40 and an internal sectional area Aheader of the lower header 30 may be approximately 0.7 times or more as large as a sum 10×7×A of sectional areas of flow paths.

The internal sectional area Aheader of the upper header 40 and the internal sectional area Aheader of the lower header 30 will be described in more detail with reference to FIG. 12.

In the heat exchanger for an air conditioner according to embodiments, a separator 39 may be disposed between the second lower flow path PL2 formed at or in the lower header 30 of the first heat exchange device HU1 of the plurality of heat exchange devices HU1 and HU2 and the second lower flow path PL2 formed at or in the lower header 30 of the second heat exchange device HU2 of the plurality of heat exchange devices HU1 and HU2. The separator 39 may separate the second lower flow path PL2 formed at or in the lower header 30 of first heat exchange device HU1 from the second lower flow path PL2 formed at or in the lower header 30 of the second heat exchange device HU2. The separator 39 may be provided therein with a plurality of communication holes 35, 36, 37, and 38. A sum of sectional areas of the plurality of communication holes 35, 36, 37, and 38 may be approximately 4% to approximately 8% of an area of the separator 39.

The plurality of communication holes 35, 36, 37, and 38 may be formed in the lower header 30 of each of the plurality of heat exchange devices HU1 and HU2. The plurality of communication holes 35, 36, 37, and 38 may be spaced apart from each other in a longitudinal direction of the lower header 30. The sum of sectional areas of the plurality of communication holes 35, 36, 37, and 38 will be described in more detail with reference to FIG. 14.

Hereinafter, a case in which the heat exchanger for an air conditioner according to embodiments includes a front or first exchanger device HU1 to which an inlet pipe 100 is connected and a rear or second heat exchanger device HU2 to which an outlet pipe 110 is connected will be described in detail. Hereinafter, the lower header 30 of the front exchange device HU1 may be referred to as ‘lower front header’, the plurality of flat tubes 50 and 70 of the front exchange device HU1 may be referred to as ‘a plurality of front flat tubes’, and the upper header 40 of the front exchange device HU1 may be referred to as ‘upper front header’. Further, the lower header 30 of the rear heat exchange device HU2 may be referred to as ‘lower rear header’, the plurality of flat tubes 50 and 70 of the rear heat exchange device HU2 may be referred to as ‘a plurality of rear flat tubes’, and the upper header 40 of the rear heat exchange device HU2 may be referred to as ‘upper rear header’.

In the heat exchanger for an air conditioner according to embodiments, the lower front header may be bonded with the lower rear header. The upper front header may be bonded with the upper rear header. The plurality of front flat tubes may be spaced apart from the plurality of rear flat tubes in an air flow direction.

In the heat exchanger for an air conditioner according to embodiments, a portion of plates to which the lower front header and the lower rear header may be bonded may serve as the separator 39 in which the communication holes 35, 36, 37, and 38 may be formed. When a rear plate of the front heat exchange device HU1 is bonded with a front plate of the rear heat exchanger device HU2, each of the rear plate of the front heat exchange device HU1 and the front plate of the rear heat exchange device HU2 may include the separator 39 in which the plurality of communication holes 35, 36, 37, and 38 may be formed.

In the heat exchanger for an air conditioner according to embodiments, the refrigerant may be introduced into the first lower flow path PL1 of the lower front header from the inlet pipe 100 so that the refrigerant may be sprayed into the first lower flow path PL1 of the lower front header. Next, the refrigerant may pass through the first front flat tube group 50 and be moved upwards. The refrigerant may be moved to the upper flow path PU of the upper front header, and may be horizontally moved to an upper side of the second front flat tube group 70. Next, the refrigerant may pass through the second front flat tube group 70 and be moved downward, and may be moved to the second lower flow path PL2 of the lower front header. The moving direction of the refrigerant moved to the second lower flow path PL2 of the lower front header may be changed inside the second lower flow path PL2 of the lower front header. After that, the refrigerant may be sprayed through the plurality of communication holes 35, 36, 37, and 38 to pass through the separator 39. The refrigerant may be partially evaporated in the front exchange device HU1 and be sprayed through the plurality of communication holes 35, 36, 37, and 38, to be moved to the rear heat exchange device HU2. The sprayed refrigerant passing through the plurality of communication holes 35, 36, 37, and 38 may be introduced into the second lower flow path PL2 of the lower rear header.

The refrigerant introduced into the second lower flow path PL2 of the lower rear header may pass through the second rear flat tube group 70 and be moved upward. The refrigerant may be moved to the upper flow path PU of the upper rear header, and may be horizontally moved to an upper side of the first rear flat tube group 50. The refrigerant may pass through the first rear flat tube group 50 and be moved downward, and may be moved to the first lower flow path PL1 of the lower rear header.

The refrigerant moved to the first lower flow path PL1 of the lower rear header may be introduced into the outlet pipe 110 and pass therethrough. Heat of the refrigerant may be sequentially exchanged with air in the front exchange device HU1 and the rear heat exchanger device HU2 and the exchanged refrigerant may be moved to the flow path 11.

FIG. 10 is a graph illustrating a performance ratio of a heat exchanger according to a length ratio of a longitudinal width of a heat exchange region to a transverse width of the heat exchange region in a heat exchanger for an air conditioner according to an embodiment. When a longitudinal width L of the heat exchange area Aheat is greater than a transverse area W thereof, the performance ratio in the heat exchanger for an air conditioner according to embodiments may be improved. The longitudinal width L of the heat exchange area Aheat may be approximately 1.5 times or more as large as the transverse area W thereof. The longitudinal width L of the heat exchange area Aheat may be approximately 2.5 times or less as large as the transverse area W thereof. Hereinafter, a ratio of the longitudinal width L to the transverse area W may be referred to as a length ratio.

As the length of the plurality of flat tubes 50 and 70 is increased in a state in which a transverse width of the lower header 30 and a transverse width of the upper header 40 are constant, the performance ratio in the heat exchanger for an air conditioner according to embodiments may be improved. As the length of the plurality of flat tubes 50 and 70 is increased, a heat transfer area in the heat exchanger for an air conditioner according to embodiments may be increased.

In a state in which the transverse width W of the heat exchange area Aheat is constant in the heat exchanger for an air conditioner according to embodiments, a longitudinal width L of a heat exchange area Aheat having the best heat exchange performance ratio may be determined by experiment. The heat exchange performance ratio in the heat exchanger for an air conditioner according to a length ratio L/2 may be determined by experiment based on the longitudinal width W having the best heat exchange performance ratio. In a state in which other factors, such as an amount of wind blown to the heat exchanger during the experiment and a mass flow rate of the refrigerant affecting the performance of the heat exchanger, are constant, the performance of the heat exchanger may be determined by varying a sectional area ratio, and experimental results are illustrated in FIG. 10.

As shown in FIG. 10, when the length ratio L/W is approximately 2.4, the heat exchanger for an air conditioner according to embodiments may represent a maximum heat exchange performance ratio. A length ratio L/W capable of representing approximately 95% of the maximum heat exchange performance ratio based on the heat exchange performance of approximately 100% may be confirmed. The performance ratio in the heat exchanger for an air conditioner may be determined by varying only the length ratio L/W. When the length ratio L/W is approximately 1.5, the heat exchanger for an air conditioner according to embodiments may present a heat exchange performance of approximately 98% based on the maximum heat exchange performance. When the length ratio L/W is approximately 1.0, the heat exchanger of the air conditioner may represent a heat exchange performance ratio of approximately 95% based on the maximum heat exchange performance ratio. The heat exchanger for an air conditioner according to embodiments may be designed so that the length ratio L/W is in the range of approximately 1 to approximately 1.5.

FIG. 11 is a sectional view of an inside of a header of a heat exchanger for an air conditioner according to an embodiment. FIG. 12 is a graph illustrating a mal-distribution ratio according to a ratio of a sum of sectional areas of flow paths of a plurality of flat tubes forming one path to an internal sectional area of a header according to an embodiment.

When each of the internal sectional area of the upper header 40 and the internal sectional area of the lower header 30 is approximately 0.7 times or more as large as a sum of sectional areas of flow paths of the plurality of flat tubes forming one path, the number of excessively heated tubes may be minimized. The excessively heated tubes may be a flat tube excessively heated when refrigerant is not uniformly distributed to the plurality of flat tubes.

The internal sectional area of the upper header 40 may be an internal sectional area in a direction perpendicular to a longitudinal direction of the upper header 40, and may be a sectional area of the upper flow path PU. The internal sectional area of the upper header 30 may be an internal sectional area in a direction perpendicular to a longitudinal direction of the lower header 30, and may be a sectional area of the first lower flow path PL1 or a sectional area of the second lower flow path PL2. The internal sectional area Aheader of the upper header 40 and the internal sectional area Aheader of the lower header 30 may be approximately 0.8 times or less as large as a sum Acell of sectional areas of flow paths.

Hereinafter, the internal sectional area of the upper header 40 and the internal sectional area of the lower header 30 may be referred to as an internal sectional area Aheader of the header. Further, a ratio Aheader/Acell of the internal sectional area Aheader of the header to a sum Acell of sectional areas of flow paths of the plurality of flat tubes may be referred to as a sectional area ratio.

In the heat exchanger for an air conditioner according to embodiments, the number of excessively heated tubes may be changed according to the sectional area ratio. If a sectional area of the upper flow path PU, a sectional area of the first lower flow path PL1, and a sectional area Aheader of the second lower flow path PL2 are increased in a state in which a sum Acell of sectional areas of flow paths in the plurality of flat tubes 50 and 70 is constant, a mal-distribution ratio % may be reduced in the heat exchanger for an air conditioner according to embodiments. If a sum Acell of sectional areas of flow paths in the plurality of flat tubes 50 and 70 is increased in a state in which a sectional area of the upper flow path PU, a sectional area of the first lower flow path PL1, and a sectional area Aheader of the second lower flow path PL2 are constant, a mal-distribution ratio % may be increased in the heat exchanger.

A sectional area ratio where an excessively heated tube is minimized or is not generated according to the sectional area ratio may be determined by experiment in the heat exchanger for an air conditioner according to embodiments. In a state in which other factors, such as an amount of wind blown to the heat exchanger for an air conditioner according to embodiments and a mass flow rate of the refrigerant affecting the performance of the heat exchanger are constant, the number of excessively heated tubes may be determined by varying only the sectional area ratio, and experimental results are illustrated in FIG. 12.

In the heat exchanger for an air conditioner according to embodiments, a range of the sectional area ratio may be determined in a case in which an excessively heated tube of a suitable level based on a sectional area ratio in which the excessively heated tube is minimized. When the sectional area ratio is about 0.78 in the heat exchanger for an air conditioner according to embodiments, the excessively heated tube may not occur or may be minimized. When the heat exchanger for an air conditioner according to embodiments has the sectional area ratio of about 0.67, it may be confirmed by experiment that excessively heated tubes of approximately 10% among a plurality of flat tubes are caused. If the heat exchanger for an air conditioner according to embodiments has the sectional area ratio of at least approximately 0.7, as flat tubes of approximately 10% or less among the flat tubes may become excessively heated, the sectional area ratio may be 0.7 or greater. The heat exchanger for an air conditioner according to embodiments may have a sectional area ratio of at least approximately 0.8.

FIG. 13 is a front view of a plurality of communication holes and a separator according to an embodiment. FIG. 14 is a graph illustrating a cooling efficiency according to a ratio of an area of a separator to a sum of sectional areas of a plurality of communication holes in a heat exchanger for an air conditioner according to an embodiment.

An area As of the separator 39 may be determined based on a height H of the second lower flow path PL2 and a longitudinal width K of a lower header in the second lower flow path PL2. The plurality of communication holes 35, 36, 37, and 38 may have the same or different sectional areas. When the plurality of communication holes has the same sectional area, a sum Au of sectional areas of the plurality of communication holes 35, 36, 37, and 38 may be determined as (π D2/4×N), where D is a diameter of a communication hole, and N is a number of communication holes 35, 36, 37, and 38 formed in the separator 39. A ratio (Au/As) of the area As of the separator 39 of the sum Au of sectional areas of the plurality of communication holes 35, 36, 37, and 38 may be (π D2/4×N)/(H×K). When the refrigerant passes through the plurality of communication holes 35, 36, 37, and 38 shown in FIG. 13, mist flow may occur due to an orifice effect.

If the sectional areas of the plurality of communication holes 35, 36, 37, and 38 are excessively small in the heat exchanger for an air conditioner according to embodiments, a load of a compressor may be increased and efficiency may be deteriorated due to an increase in pressure loss. If the sectional areas of the plurality of communication holes 35, 36, 37, and 38 are excessively large in the heat exchanger for an air conditioner according to embodiments, the refrigerant may not be uniformly distributed to the plurality of communication holes 35, 36, 37, and 38, and efficiency may be deteriorated due to unbalance of the refrigerant.

It may be confirmed by experiment that the plurality of communication holes 35, 36, 37, and 38 have sectional areas capable of maximizing a cooling performance of the heat exchanger for an air conditioner according to embodiments. The cooling performance in the heat exchanger for an air conditioner according to embodiments may be confirmed by varying the sum of sectional areas of the plurality of communication holes 35, 36, 37, and 38 as compared with the area of the separator 39.

FIG. 14 is a graph illustrating a cooling efficiency according to a ratio of an area of a separator to a sum of sectional areas of a plurality of communication holes in a heat exchanger of an air conditioner according to an embodiment. That is, FIG. 14 illustrates an experimental result measuring a cooling performance by allowing other factors affecting the cooling performance to have the same value and by differently varying only the sum of sectional areas of the plurality of communication holes 35, 36, 37, and 38. Hereinafter, a ratio Au/As of the area Au of the separator 39 to the sum Au of sectional areas of the plurality of communication holes 35, 36, 37, and 38 may be referred to as a communication hole area ratio.

As shown in FIG. 14, with the communication hole area ratio Au/As in section Q of approximately 0.04 to approximately 0.08, the heat exchanger for an air conditioner according to embodiments may represent a higher cooling performance in comparison with the other sections P and R. When the communication hole area ratio Au/As is in section P, that is, it is less than approximately 0.04, a sum of sectional areas of the plurality of communication holes are too small as compared with the area of the separator As, so that efficiency in the heat exchanger for an air conditioner according to embodiments may be deteriorated due to pressure loss. When the communication hole area ratio Au/As is in section R, that is, it exceeds approximately 0.08, the efficiency in the heat exchanger for an air conditioner according to embodiments may be deteriorated due to unbalance of the refrigerant.

The sum Au of sectional areas of the plurality of communication holes 35, 36, 37, and 38 may be approximately 4% to approximately 8% of the area As of the separator 39. Moreover, the sum Au of sectional areas of the plurality of communication holes 35, 36, 37, and 38 may be approximately 5% to approximately 7% of the area As of the separator 39.

FIG. 15 is a perspective view of a heat exchanger for an air conditioner according to another embodiment. FIG. 16 is an exploded perspective view of the heat exchanger of FIG. 15. FIG. 17 is a sectional plan view of an upper header of the heat exchanger of FIG. 15. FIG. 18 is a sectional plan view of a lower header of the heat exchanger of FIG. 15.

In the heat exchanger for an air conditioner according to this embodiment, a plurality of heat exchange devices HU1′ and HU2′ may be disposed at front and rear sides in an air moving direction. An upper header 40′ of a first heat exchange device HU1′ may be partitioned into a first upper flow path PU1 and a second upper flow path PU2. That is, an inside of the upper header 40′ of the first heat exchange device HU1′ may be partitioned into the first upper flow path PU1 and the second upper flow path PU2 by a partition 43.

An inlet pipe 100 that introduces and guides the refrigerant may be connected to the first upper flow path PU1 of the first heat exchange device HU1′. An outlet pipe 110 that discharges and guides the refrigerant may be connected to the second upper flow path PU2 of the first heat exchange device HU1′.

As illustrated with this embodiment, one upper flow path PU may be longitudinally formed in a longitudinal direction of an upper header 40 of the second heat exchange device HU2′. The inlet pipe 100 and the outlet pipe 110 may not be connected to the first heat exchange device HU1′. A first lower flow path PL1 formed at or in a lower header 30′ of the first heat exchange device HU1′ may communicate with a first lower flow path PL1 formed at or in a lower header 30′ of the second heat exchange device HU2′ through a plurality of first communication holes 35′, 36′, 37′, and 38′.

A first separator 39′ may be disposed between the first lower flow path PL1 formed at or in the lower header 30′ of the first heat exchange device HU1′ and the first lower flow path PL1 formed at or in the lower header 30′ of the second heat exchange device HU2′. The first separator 39′ may be formed therein with the plurality of first communication holes 35′, 36′, 37′, and 38′.

A sum of sectional areas of the plurality of communication holes 35′, 36′, 37′, and 38′ may be approximately 4% to approximately 8% of an area of the first separator 39′. An effect according to the sum of sectional areas of the plurality of communication holes 35′, 36′, 37′, and 38′ and the area of the first separator 39′ may be identical or similar to that of the previous embodiment, and thus detailed description thereof has been omitted.

A second lower flow path PL2 formed at or in a lower header 30′ of the first heat exchange device HU1′ may communicate with a second lower flow path PL2 formed at or in a lower header 30′ of the second heat exchange device HU2′ through a plurality of communication holes 35, 36, 37, and 38.

A second separator 39 may be disposed between the second lower flow path PL2 formed at or in the lower header 30 of the first heat exchange device HU1′ and the second lower flow path PL2 formed at or in the lower header 30 of the second heat exchange device HU2′. The second separator 39 may be formed therein with the plurality of communication holes 35, 36, 37, and 38.

A sum of sectional areas of the plurality of communication holes 35, 36, 37, and 38 may be approximately 4% to approximately 8% of an area of the second separator 39. An effect according to the sum of sectional areas of the plurality of communication holes 35, 36, 37, and 38 and the area of the second separator 39 may be identical or similar to that of the previous embodiment, and thus detailed description thereof has been omitted.

The first and second heat exchange devices HU1′ and HU2′ may include a front exchange device HU1′, through which the refrigerant may first pass, and a rear heat exchange device HU2′, through which the refrigerant having passed through the front exchange device HU1′ may pass. A refrigerant in the flow path 10 may be introduced into a flow path of the front exchange device HU1′, pass a portion of the flow path of the front exchange device HU 1′, and be introduced into the flow path of the rear heat exchange device HU2′. The refrigerant introduced into the flow path of the rear heat exchange device HU2′ may pass through the whole flow path of the rear heat exchange device HU2′. The refrigerant having passed through the whole flow path of the rear heat exchange device HU2′ may be introduced into a remaining portion of the flow path of the front exchange device HU1′. The refrigerant having passed through the remaining portion of the flow path of the front exchange device HU1′ may be moved to a flow path 11 through the outlet pipe 110.

When comparing the heat exchanger for an air conditioner of this embodiment with the previous embodiment, the difference is that partition 43 may be formed inside of the upper header 40′ of the front exchange device HU1′ so that the front exchange device HU′ is partitioned into the first upper flow path PU1 and the second upper flow path PU2. The inlet pipe 100 may be connected to the first upper flow path PU1, rather than the first lower flow path PL1. The outlet pipe 110 may be connected to the second upper flow path PU2, rather than the second lower flow path PL2. The plurality of communication holes 35′, 36′, 37′, and 38′ may communicate the first lower flow path PL1 of the front exchange device HU1′ with the first lower flow path PL1 of the rear heat exchange device HU2′. Other configurations are the same as those of the previous embodiment, and thus, detailed description thereof has been omitted.

The front exchange device HU1′ may include a first front flat tube group 50 that communicates the first upper flow path PU1 formed at or in the upper header 40′ of the front exchange device HU1′ with the first lower flow path PL1 formed at or in the lower header 30′ of the front exchange device HU1′. The front exchange device HU1′ may include a second front flat tube group 70 that communicates the second lower flow path PL2 formed at or in the lower header 30′ of the front exchange device HU1′ with the second upper flow path PU2 formed at or in the upper header 40′ of the front exchange device HU1′.

The rear heat exchange device HU2′ may include a first rear flat tube group 50 that communicates the first lower flow path PL1 formed at or in the lower header 30′ of the rear heat exchange device HU2′ with the upper flow path PU formed at or in the upper header 40 of the rear heat exchange device HU2′. The rear heat exchange device HU2′ may include a second rear flat tube group 70 that communicates the upper flow path PU formed at or in the upper header 40 of the rear heat exchange device HU2′ with the second lower flow path PL2 formed at or in the lower header 30′ of the rear heat exchange device HU2′.

Hereinafter, a case in which a heat exchanger for an air conditioner according to embodiments includes a front exchange device HU1′ connected to the inlet pipe 100 and the outlet pipe 110 and a rear heat exchange device HU2′ not connected to the inlet pipe 100 and the outlet pipe 110 will be described in detail.

Hereinafter, the lower header 30′ of the front exchange device HU1′ may be referred to as a lower front header. The plurality of flat tubes 50 and 70 of the front exchange device HU1′ may be referred to as a plurality of front flat tubes. An upper header 40′ of the front exchange device HU1′ may be referred to as an upper front header.

Further, the lower header 30′ of the rear heat exchange device HU2′ may be referred to as a lower rear header. The plurality of flat tubes 50 and 70 of the rear heat exchange device HU2′ may be referred to as a plurality of rear heat flat tubes. The upper header 40 of the rear heat exchange device HU2′ may be referred to as an upper rear header.

In the heat exchanger for an air conditioner according to embodiments, the front lower header may be bonded with the rear lower header. The front upper header may be bonded with the rear upper header. The plurality of front flat tubes may be spaced from the plurality of rear heat flat tubes in the air moving direction.

In the heat exchanger for an air conditioner according to embodiments, a plate at which the front lower header and the rear lower header are bonded to each other may include the first separator 39′ formed therein with the plurality of communication holes 35′, 36′, 37′, and 38′ and the second separator 39 formed therein with the plurality of communication holes 35, 36, 37, and 38. When a rear plate of the front lower header of the front exchange device HU1′ is bonded with a front plate of the rear lower header of the rear heat exchange device HU2′, the rear plate of the front lower header of the front exchange device HU1′ may be formed therein with the plurality of communication holes 35′, 36′, 37′, and 38′, and the front plate of the rear lower header of the rear heat exchange device HU2′ may be formed therein with the plurality of communication holes 35, 36, 37, and 38. The plurality of communication holes 35′, 36′, 37′, and 38′ and the plurality of communication holes 35, 36, 37, and 38 may be separately formed at or in the separators 39′ and 39, respectively.

The first separator 39′ may be formed between the first lower flow path PL1 of the front lower front header and the first lower flow path PL1 of the rear lower header. The refrigerant in the first lower flow path PL1 of the lower front header may be distributed to the plurality of communication holes 35′, 36′, 37′, and 38′ formed in the first separator 39′ and may be moved to the first lower flow path PL1 of the rear lower header.

The second separator 39 may be formed between the second lower flow path PL2 of the rear lower header and the second lower flow path PL1 of the front lower header. The refrigerant in the second lower flow path PL2 of the rear lower header may be distributed to the plurality of communication holes 35, 36, 37, and 38 formed in the second separator 39 and may be moved to the second lower flow path PL2 of the front lower header. The second separator 39 may be the same as the separator 39 of the previous embodiment. The plurality of communication holes 35, 36, 37, and 38 may be the same as the plurality of communication holes 35, 36, 37, and 38 of the previous embodiment. What is different from the previous embodiment may be a direction in which the refrigerant passes.

In the heat exchanger for an air conditioner according to this embodiment, the refrigerant may be introduced into the first upper flow path PU1, be sprayed to the first upper flow path PU1 of the front upper header 40′, pass through the first front flat tube group 50 and be moved downward. The refrigerant may be moved to the first lower flow path PL1 of the front lower header 30′, and a moving direction of the refrigerant may be changed in the first lower flow path PL1 of the front lower header 30′. The refrigerant located in the first lower flow path PL1 of the front lower header 30′ may be sprayed to or through the plurality of communication holes 35′, 36′, 37′, and 38′ and pass through the first separator 39′. The refrigerant sprayed by passing through the plurality of communication holes 35′, 36′, 37′, and 38′ may be introduced into the first lower flow path PL1 of the rear lower header 30′.

The refrigerant introduced into the first lower flow path PL1 of the rear lower header may pass through the first rear flat tube group 50 and be moved upward. Next, the refrigerant may be moved to the upper flow path PU of the rear upper header 40, and may be horizontally moved to the second rear flat tube group 70.

Next, the refrigerant may pass through the second rear flat tube group 70 and be moved downward, and be moved to the second lower flow path PL2 of the rear lower header 30′. A moving direction of the refrigerant moved to the second lower flow path PL2 of the rear lower header 30′ may be changed. The refrigerant in the second lower flow path PL2 of the rear lower header 30′ may be sprayed to or through the plurality of communication holes 35, 36, 37, and 38 and pass through the second separator 39. The refrigerant sprayed by passing through the plurality of communication holes 35, 36, 37, and 38 may be introduced into the second lower flow path PL2 of the front lower header 30′.

The refrigerant introduced into the second lower flow path PL2 of the front lower header 30′ may pass through the second front flat tube group 70 and be move upward. The refrigerant moved to the second front flat tube group 70 may be moved to the second upper flow path PU2 of the front upper header 40′. Next, the refrigerant moved to the second upper flow path PU2 of the front upper header 40′ may be introduced and pass through the outlet pipe 110. In this manner, in a state in which heat of the refrigerant may sequentially be exchanged with air in a portion of the front exchange front HU1′, the rear heat exchange front HU2, and a remaining portion of the front exchange front HU1′, the refrigerant may be moved to the flow path 11.

In the following description of the flow of the refrigerant, the first upper flow path PU1 of the front upper header may be referred to as a first upper front flow path, the first lower flow path PL1 of the lower front header may be referred to as a first lower front flow path, the first lower flow path PL1 of the lower rear header may be referred to as a first lower rear flow path, the second lower flow path PL2 of the lower rear header may be referred to as a second lower rear flow path, the second lower flow path PL2 of the lower front header may be referred to as a second lower front flow path, the second upper flow path PL2 of the upper front header may be referred to as a second upper front flow path. The refrigerant in the flow path 10 may sequentially pass through first upper front flow path, the first front flat tube group, and the first lower front flow path in the inlet pipe 100 to pass through a partial flow path of the front heat exchange device HU1′.

The refrigerant in the first lower front flow path may be introduced into the first lower rear path through the plurality of communication holes 35′, 36′, 37′, and 38′ and be moved to the rear heat exchange device HU2′. The refrigerant in the first lower rear flow path may sequentially pass through the first rear flat tube group, the upper flow path, the second rear flat tube group, and the second lower rear flow path to pass through the rear heat exchange device HU2′.

The refrigerant in the second lower rear flow path may be introduced into the second lower front path through the plurality of communication holes 35, 36, 37, and 38 and be moved to the front heat exchange device HU1′. The refrigerant in the second lower front flow path may sequentially pass through the second front flat tube group and the upper flow path to pass through a remaining flow path of the front heat exchange device HU1′. The refrigerant in the second upper front flow path may be move to the flow path 11 through the outlet pipe 110.

Embodiments disclosed herein provide a heat exchanger of an air conditioner capable of uniformly distributing a refrigerant to a plurality of flat tubes and improving heat exchanging performance.

Embodiments disclosed herein provide a heat exchanger of an air conditioner that may include a lower header provided therein with a lower flow path; an upper header provided therein with an upper flow path; a plurality of flat tubes provided therein with a plurality of flow paths that communicates with the lower flow path and the upper flow path; and a heat exchange unit or device including fins disposed between the plurality of flat tubes. The upper flow path may be partitioned into a first lower flow path with which some of the plurality of flat tubes may communicate, and a second lower flow path with which remaining tubes of the plurality of flat tubes may communicate. A longitudinal width of a heat exchange area may be greater than a transverse width of the heat exchange area, the heat exchange area being an area where heat of the plurality of flat tubes and the fins may be exchanged with air, and each of an internal sectional area of the upper header and an internal sectional area of the lower header may be approximately 0.7 times or more as large as a sum of sectional areas of flow paths in the plurality of flat tubes constituting one path.

A refrigerant introduced into the upper flow path through the some of the plurality of flat tubes may collide with an upper inner wall of the upper header and be discharged to the remaining tubes of the plurality of flat tubes. The heat exchanger may further include an inlet pipe to introduce and guide a refrigerant in a direction perpendicular to the plurality of flat tubes.

The inlet pipe may communicate with one of the first lower flow path or the second lower flow path. The inlet pipe may include a plurality of branch pipes.

The sum of sectional areas of flow paths may be determined by the following Equation 1:

Acell=Tn×Cn×A  [Equation 1]

where, Acell is a sum of areas of the flow paths, Tn is a number of flat tubes constituting one path, Cn is a number of flow paths formed at the plurality of flat tubes, and A is an area of a flow path.

Each of an internal sectional area of the upper header and an internal sectional area of the lower header may be approximately 0.8 times or less as large as a sum of sectional areas of flow paths. The longitudinal width may be approximately 1.5 times or more as large as the transverse width. The longitudinal width may be approximately 2.5 times or less as large as the transverse width.

A plurality of heat exchange units or devices may be disposed in front and rear sides in an air moving direction front and back, an inlet pipe that introduces and guides a refrigerant may be connected to a first lower flow path formed at one lower header among the plurality of heat exchange units, and an outlet pipe that introduces and guides the refrigerant may be connected to an outlet flow path formed at a lower header of a remaining one of the plurality of heat exchange units.

A separator may be disposed between a second lower flow path formed at one lower header among the plurality of heat exchange units, and a second lower flow path formed at another lower header among the plurality of heat exchange units, and may be provided therein with a plurality communication holes.

A sum of sectional areas of the plurality of communication holes may be approximately 4% to approximately 8% of an area of the separator.

A plurality of heat exchange units may be disposed in front and rear sides in an air moving direction, and an upper flow path formed at ban upper header of one of the plurality of heat exchange units may be partitioned into a first upper flow path and a second upper flow path.

An inlet pipe that introduces and guides a refrigerant may be connected of the first upper flow path, and an outlet pipe that discharges and guides the refrigerant may be connected to the second upper flow path.

A first lower flow path formed at a lower header of one of the plurality of heat exchange units may communicate with a first lower flow path formed at a lower header of a remaining one of the plurality of heat exchange units through a plurality of first communication holes, and a second lower flow path formed at the lower header of the one of the plurality of heat exchange units may communicate with a second lower flow path formed at the lower header of the remaining one of the plurality of heat exchange units through a plurality of second communication holes.

A sum of sectional areas of the plurality of first communication holes may be approximately 4% to approximately 8% of an area of a separator which is disposed between a first lower flow path formed at a lower header of one of the plurality of heat exchange units and a first lower flow path formed at a lower header of a remaining one of the plurality of heat exchange units.

A sum of sectional areas of the plurality of second communication holes may be approximately 4% to approximately 8% of an area of a separator which is disposed between a second lower flow path formed at a lower header of one of the plurality of heat exchange units and a second lower flow path formed at a lower header of a remaining one of the plurality of heat exchange units.

The heat exchanger for an air conditioner according to embodiments may uniformly distribute refrigerant to a plurality of flat tubes to prevent the plurality of flat tubes from being excessively heated.

An optimal ratio of a sum of sectional areas of a plurality of communication holes to an area of a separator formed therein with the plurality of communication holes may be provided.

A divider or a capillary tube may not be separately installed outside of the exchanger for an air conditioner, and occurrence of excessively heated tubes may be minimized while increasing heat exchange performance at a low cost.

Any reference in this specification to “one embodiment,” “an embodiment,” “example embodiment,” etc., means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. The appearances of such phrases in various places in the specification are not necessarily all referring to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with any embodiment, it is submitted that it is within the purview of one skilled in the art to effect such feature, structure, or characteristic in connection with other ones of the embodiments.

Although embodiments have been described with reference to a number of illustrative embodiments thereof, it should be understood that numerous other modifications and embodiments can be devised by those skilled in the art that will fall within the spirit and scope of the principles of this disclosure. More particularly, various variations and modifications are possible in the component parts and/or arrangements of the subject combination arrangement within the scope of the disclosure, the drawings and the appended claims. In addition to variations and modifications in the component parts and/or arrangements, alternative uses will also be apparent to those skilled in the art. 

What is claimed is:
 1. A heat exchanger for an air conditioner, comprising: at least one heat exchange device, the at least one heat exchange device comprising: a lower header provided therein with a lower flow path; an upper header provided therein with an upper flow path; and a plurality of flat tubes provided therein with a plurality of flow paths that communicates with the lower flow path and the upper flow path, wherein the upper flow path is partitioned into a first lower flow path with which a first portion of the plurality of flat tubes communicates, and a second lower flow path with which a second portion of the plurality of flat tubes communicates, wherein a longitudinal width of a heat exchange area is greater than a transverse width of the heat exchange area, the heat exchange area being an area in which heat of the plurality of flat tubes are exchanged with air, and wherein each of an internal sectional area of the upper header and an internal sectional area of the lower header is approximately 0.7 times or more as large as a sum of sectional areas of flow paths in the plurality of flat tubes forming one path.
 2. The heat exchanger of claim 1, wherein the at least one heat exchange device further comprises a plurality of fins disposed between the plurality of flat tubes.
 3. The heat exchanger of claim 1, wherein a refrigerant introduced into the upper flow path through the first portion of the plurality of flat tubes collides with an upper inner wall of the upper header and is discharged to the second portion of the plurality of flat tubes.
 4. The heat exchanger of claim 1, further comprising an inlet pipe to introduce and guide a refrigerant into the heat exchanger in a direction substantially perpendicular to a direction in which the plurality of flat tubes extends.
 5. The heat exchanger of claim 4, wherein the inlet pipe communicates with one of the first lower flow path or the second lower flow path.
 6. The heat exchanger of claim 4, wherein the inlet pipe comprises a plurality of branch pipes.
 7. The heat exchanger of claim 1, wherein the sum of the sectional areas of the flow paths is determined by the following equation: Acell=Tn×Cn×A where, Acell is the sum of the sectional areas of the flow paths, Tn is a number of flat tubes forming one path, Cn is a number of the flow paths formed in the plurality of flat tubes forming the one path, and A is an area of a flow path.
 8. The heat exchanger of claim 1, wherein each of the internal sectional area of the upper header and the internal sectional area of the lower header is approximately 0.8 times or less as large as the sum of the sectional areas of the flow paths.
 9. The heat exchanger of claim 1, wherein the longitudinal width is approximately 1.5 times or more as large as the transverse width.
 10. The heat exchanger of claim 9, wherein the longitudinal width is approximately 2.5 times or less as large as the transverse width.
 11. The heat exchanger of claim 1, wherein the at least heat exchange device comprises a plurality of heat exchange devices disposed at front and rear sides with respect to an air moving direction, wherein an inlet pipe that introduces and guides a refrigerant into the heat exchanger is connected to a first lower flow path formed in a lower header of a first heat exchange device of the plurality of heat exchange devices, and wherein an outlet pipe that introduces and guides the refrigerant out of the heat exchanger is connected to a lower flow path formed in a lower header of a second heat exchange device of the plurality of heat exchange devices.
 12. The heat exchanger of claim 11, wherein a separator is disposed between a second lower flow path formed in the lower header of the first heat exchange device, and a second lower flow path formed in the lower header of the second heat exchange device, and is provided therein with a plurality communication holes.
 13. The heat exchanger of claim 12, wherein a sum of sectional areas of the plurality of communication holes is approximately 4% to approximately 8% of an area of the separator.
 14. The heat exchanger of claim 1, wherein the at least heat exchange device comprises a plurality of heat exchange devices disposed at front and rear sides with respect to an air moving direction, and wherein an upper flow path formed in an upper header of a first heat exchange device of the plurality of heat exchange devices is partitioned into a first upper flow path and a second upper flow path.
 15. The heat exchanger of claim 14, wherein an inlet pipe that introduces and guides a refrigerant into the heat exchanger is connected to the first upper flow path, and an outlet pipe that discharges and guides the refrigerant from the heat exchanger is connected to the second upper flow path.
 16. The heat exchanger of claim 15, wherein a first lower flow path formed in a lower header of the first heat exchange device communicates with a first lower flow path formed in a lower header of a second heat exchange device of the plurality of heat exchange devices through a plurality of first communication holes, and wherein a second lower flow path formed in the lower header of the first heat exchange device communicates with a second lower flow path formed in the lower header of the second heat exchange device through a plurality of second communication holes.
 17. The heat exchanger of claim 16, wherein a sum of sectional areas of the plurality of first communication holes is approximately 4% to approximately 8% of an area of a separator, which is disposed between the first lower flow path formed in the lower header of the first heat exchange device and the first lower flow path formed in the lower header of the second heat exchange device.
 18. The heat exchanger of claim 17, wherein a sum of sectional areas of the plurality of second communication holes is approximately 4% to approximately 8% of an area of a separator, which is disposed between the second lower flow path formed in the lower header of the first heat exchange device and the second lower flow path formed in the lower header of the second heat exchange device.
 19. An air conditioner comprising the heat exchanger of claim
 1. 20. A heat exchanger for an air conditioner, comprising: least one heat exchange device, the at least one heat exchange device comprising: a lower header provided therein with a lower flow path; an upper header provided therein with an upper flow path; and a plurality of flat tubes provided therein with a plurality of flow paths that communicates with the lower flow path and the upper flow path, wherein the upper flow path is partitioned into a first upper flow path with which a first portion of the plurality of flat tubes communicates, and a second upper flow path with which a second portion of the plurality of flat tubes communicates, and wherein each of an internal sectional area of the upper header and an internal sectional area of the lower header is approximately 0.7 times or more as large as a sum of sectional areas of flow paths in the plurality of flat tubes forming one path.
 21. The heat exchanger of claim 20, wherein the at least one heat exchange device further comprises a plurality of fins disposed between the plurality of flat tubes.
 22. The heat exchanger of claim 20, wherein the sum of the sectional areas of the flow paths may be determined by the following equation: Acell=Tn×Cn×A where, Acell is the sum of the sectional areas of the flow paths, Tn is a number of flat tubes forming one path, Cn is a number of the flow paths formed in the plurality of flat tubes forming the one path, and A is an area of a flow path.
 23. The heat exchanger of claim 20, wherein each of an internal sectional area of the upper header and an internal sectional area of the lower header is approximately 0.8 times or less as large as the sum of the sectional areas of the flow paths.
 24. An air conditioner comprising the heat exchanger of claim
 20. 25. A heat exchanger for an air conditioner, comprising: at least one heat exchange device, the at least one heat exchange device comprising: a lower header provided therein with a lower flow path; an upper header provided therein with an upper flow path; and a plurality of flat tubes provided therein with a plurality of flow paths that communicates with the lower flow path and the upper flow path, wherein the plurality of flat tubes are divided into a plurality of groups, each group forming one path in communication with a portion of the lower flow path and the upper flow path, wherein a longitudinal width of a heat exchange area is greater than a transverse width of the heat exchange area, the heat exchange area being an area in which heat of the plurality of flat tubes are exchanged with air, and wherein each of an internal sectional area of the upper header and an internal sectional area of the lower header is approximately 0.7 times or more as large as a sum of sectional areas of flow paths in the plurality of flat tubes forming one path.
 26. The heat exchanger of claim 25, wherein the at least one heat exchange device further comprises a plurality of fins disposed between the plurality of flat tubes.
 27. The heat exchanger of claim 25, wherein the sum of the sectional areas of the flow paths may be determined by the following equation: Acell=Tn×Cn×A where, Acell is the sum of the sectional areas of the flow paths, Tn is a number of flat tubes forming one path, Cn is a number of the flow paths formed in the plurality of flat tubes forming the one path, and A is an area of a flow path.
 28. The heat exchanger of claim 25, wherein each of an internal sectional area of the upper header and an internal sectional area of the lower header is approximately 0.8 times or less as large as the sum of the sectional areas of the flow paths.
 29. An air conditioner comprising the heat exchanger of claim
 25. 